Derivative Instruments - Additional Information (Detail) - Foreign Exchange Forward - Derivative	9 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Foreign exchange forward contracts entered	0
Foreign exchange forward contracts outstanding	0	0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration